A Pharmacokinetics, Pharmacodynamics and Safety Study of Rabeprazole in New Born Infants With Gastroesophageal Reflux Disease (GERD)

Inclusion Criteria: * Patients must need a feeding tube in place for enteral alimentation (complete or partial) and be in a neonatal intensive care unit or step down unit * Patients participating in the pHmetry assessment must be in need of this assessment * New born, neonate or pre-term infants less than 44 weeks with a minimum weight of 0.8 kg and with a presumptive diagnosis of GERD * Patients who have been treated with, or are currently receiving a proton pump inhibitor (PPI), H2-blockers or antacids * Patients should be generally healthy, other than for the presence of GERD. Exclusion Criteria: * A history of or current clinically significant medical illness (excluding GERD, asthma, reactive airway disease or cystic fibrosis-dependant GERD) * Continuous drip tube feeding with formula or breast milk * Patients whose mothers are taking PPIs and who are pumping breast milk to be fed to their infants * Continuous positive airway pressure (CPAP) delivered via nasal prong or oral mask * Serum concentrations of hepatic transaminases \> 3-fold higher than the upper limit of normal for age creatinine values = 106 micromoles/L * Clinically relevant abnormal laboratory values * Treatment with full therapeutic doses of sucralfate or any medication that affects gastrointestinal motility such as baclofen, erythromycin, metoclopramide, cisapride, or domperidone * A history of allergy or sensitivity to PPIs or to their inactive ingredients